Improved furnace for calcining ores



J. B. BRITTGN.

i Roasting Oras.

Patented )une 7, 1864.

No. L1,3003.

Inventor,

Witnesses:

Lum MM- MMM AM. PHOT0LlTHO.CD.N.Y. (USBORNE'S PROCESS) UNrTnD STATES PATENT Damon'.

J. BLODGET BRITTON, OF PHILADELPHIA, PENNSYLVANIA.

IMPROVED FURNACE FOR CALCINING ORES.

Specification forming part of Letters Patent No. 413,003. dated June 7, 186i.

To all whom, t may cof/warn.-

Be it known that I, J. BLODGET BRIT'roN, of Philadelphia, Pennsylvania, have invented certain Improvements in Furnaces for Calcining Ores, &c.; and I do hereby declare the following to be a full, clear, and exact description of the same, reference being had to the accompanying drawings, and to the letters of reference marked thereon.

My invention relates to that class of furnaces in which ores or other minerals are calcined or roasted for the purpose of driving off from the mineral such substances as are rendered gaseous or volatile by the heat; and my improvements consist, first, in a calcining-fur nace having` a fire-place so communicating with a chamber and with a ue for carrying off the products of combustion that the latter must pass across the said chamber, and thereby thoroughly heat the mass of ore in the same; secondly, in a certain arrangement of parts, or their equivalents, substantially in the manner described hereinafter, whereby masses of the'calcined ore may be discharged from the furnace.

In order to enable others skilled in the art to make and use my invention, I will now proceed to describe itsA construction and operation.

On reference to the accompanying drawings, which form a part of this specification, Figure lis a sectional elevation of my :improved furnace for calcining ores, &c.; Fig. 2, a front view; and Fig. 3, a section on the linel 2, Fig. l.

Similar lettersrefer to similar parts through out the several views.

A and A are the end walls, and B and B the side walls,` of the furnace, which is closed at'the top, with the exception of an opening, a, covered by a door, b;

In the upper part of the furnace is a reservoir, C, of such a size as will contain sufficient mineral to supply the furnace for from twelve to twenty-four hours, according to the quality of ore to be calcined, the bottom of the reservoir gradually diminishing in size to the upper end of the vertical chamber D, which gradually increases in width toward the lower end, where it communicates with a horizontal passage, E. The bottom of the passage E to- Ward the front of the furnace is cut away, so

as to form an inclined face, w, as shown in Fig. 1.

In front of the chamber D is a nre-place, F, beneath which is an ash-pit, G, the re-place communicating with the chamber D, near the top ofthe latter, through an opening, c.

Transverscly through the furnace, at the rear of the chamber D, passes afiue, H, which communicates with an adjacent chimney, and also communicates with the chamber D, through an opening, el, situated about midway between the top and bottom of the chamber. Ahorizontal perforated steam-pipe, e, extends across the front side of the chamber D, near the lower end, for a purpose described hereinafter.

The fire-place F is provided with a door, f, the ash-pit Gr being also provided with a similar door, j', below which and in front of the furnace is a suitable platform, I. The rear portion of the passage E is lined with a casing, t', to the front' of which, at the point y, is hinged a plate or door, j.

About midway between the top and bottom of the passage E, at the rear of the same, eX- tends from side to sidea platform, J, between which and the bottom of the casing@ iits snugly, but so as to slide freely, a closed metal box, K, and from each side of the latter a plate, m, projects forward to near the front end of the casing z'. A pin, n, projects from the side of each of the plates m, Fig. 3, through a slot in the side of the casing fi into a longitudinal recess in the wall B, where it is `jointed to one end of a connecting-rod, o, the other end of the rod being connected to one end of 'a slotted arm, p, on a rock-shaft, M, which turns in brackets q at the front of the furnace, on each side of the passage F.

The reservoir C and chamber D being filled with the ore to be calcined, and a fire kindled in the re-place F, a reciprocating motion is imparted by any suitable means to the rockshaft M, and steam admitted into the pipe e. As the box Kis caused to slide back and forth by the vibration of the rock-shaft M, that portion of the ore which is in the passage E, in

front of the boX K, is propelled by each forward movement of the latter toward the door j, and as the ends of the plates M come in contact with the door the latter is raised and the ore allowed to fall onto the inclined face x, down which it slides to any suitable receptacle. The products of combustion, in their passage from the fireplace F to the flue H, will take a course as nearly as possible in a direct line from the opening c downward to the opening d, passing through the mass of ore between the two openings in the chamber D. The sulphur and volatile matters disengaged by the heat from the ore are carried by the draft into the flue H, where a portion of the sulphur is deposited, the lighter gases being discharged into the chimney. As the core passes down the-chamber D, opposite the pipe e, the moist and comparatively cool steam from the latter absorbs the heat from the ore, which is thus considerl ably cooled prior to its discharge from the chamber. rIhe steam, continuing its ascent, is still further heated until it comes in contact with the highly-heated ore near the mouth d, where it is decomposed, the hydrogen combining with a portion of the sulphur to form sulphureted-hydrogen gas, while the oxygen combines with the metal and completes the oxidation begun by the heat.

rIhe furnaces now employed for calcining ores are for the most part objectionable on account of the uncertainty of their operation, there being no means by which the quantity of ore submitted in a given time to the action of the fire can be regulated, some portions of the ore being consequently overheated, while other portions are but slightly oxidized. In my improved furnace the process can be regulated with precision at every stage, and with the certainty of attaining the desired result. By'confining the ore within a narrow chamber, so that but a small quantity is submitted at one time to the action of the gases, the latter rtre brought into intimate contact with every particle of the mass of ore, instead of being scattered and irregularly diffused through the same, as in ordinary kilns, and the whole is thus thoroughly and equally heated to any desired extent.

It is well known that while some ores require to be but slightly heated in order to drive off the sulphur and oxidize them, others of a more refractory character have to be submitted to a high heat for a considerable length of time. Some qualities of ore also require little or no steaming, they being sufficiently oxidized by the heat. My improved furnace may v be so regulated that ores of either quality can ,be submitted to the treatment best adapted the ore continuously or at regular intervals,

ythe rate of descent -of the same through the chamber D may be so graduated that the time for which each particle of ore shall be submitted to the action of the ire may be regulated at pleasure, the ores being discharged slowly or at long intervals when they are exceedingly refractory, and with greater rapidity in proportion as their refractory character is diminished. The amount of steam admitted may also be varied in proportion as the ore requires to be more or less' oxidized. By increasing the width of the chamber D toward its lower end the ore is prevented from packing or arching in the chamber, its free and continuous delivery into the passage F being thereby insured.

It will be apparent that this furnace may be constructed at a slight cost, compared to that required to build many of those heretofore used for the same purpose, and that several furnaces may be placed side by side or in any suitable position adjacent to each other, the nues H of all the furnaces leading to one chimney. By this means the cost of attendance will be greatly diminished, as one or two attendants may superintend the fires of several furnaces. The discharging apparatus of all may also be driven by one engine.

Although I have described my invention as applied particularly to the calcining of ores, it will be lapparent that it may be advantageously used for calcining gypsum and other mineral substances..

Without confining myself to the precise form or arrangement of parts herein described, I claim as my invention and desire to secure by Letters Patent- 1. A calcining-furnace having a fire-place, F, communicating with a chamber, D, and with aflue for carrying off the products of combustion, so that the latter must pass across the said chamber to the said iiue, substantially as and for the purpose described.

2. The box K or its equivalent, arranged below the chamber D, in combination with the appliances herein described, or any equivalent tothe same, whereby the said box is caused to discharge masses of calcined ores, as set forth.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

J. BLODGET BRI'ITON.

XVitnesses:

GHARLEs E. FosTER, Jol-1N VHITE. 

